Year Number 2004-01-01 338 2005-01-01 337 2006-01-01 331 2007-01-01 330 2008-01-01 327 2009-01-01 325 2010-01-01 320 2011-01-01 312 2012-01-01 297 2013-01-01 283 2014-01-01 275 2015-01-01 266 2016-01-01 261